Retracted green light on GM crops feeds suspicions

[Cricket Tragic]

deek, I think you will find that I have mentioned occupational exposure. There are a number of studies on this from several countries. Largely the issue is grain dust – much in the same way as baker’s asthma occurs. This is a specific issue and doesn’t bear on the issues of people living around flowering canola crops, because they won’t be exposed to grain dust.

[prashamk]

Originally Posted by Cricket Tragic

Maybe you would like to discuss how that works on your forum?

Good luck.

In India we have a proverb;

Your politeness highlights your knowledge. Maybe you don't know about it.

[deek]

No, no CT - the study confirmed occupational sensitisation to canola pollen.

Pollen dispersal (although canola is entomophilous) cannot be contained within field boundaries. I appreciate the windborne canola pollen does not travel far (in comparison to other pollens) but it has been confirmed to travel into residential areas close to canola fields.

Scientists cannot simply argue that canola pollen causes sensitisation but this is dependant on what side of the farmer’s fence you stand. Occupational exposure limits are calculated on the basis of adult exposure over an 8 hour period. Yet, if we cross the fence into the adjacent residential estate a mother could be exposing her young children to a recognised respiratory sensitiser for considerable longer than the prescribed occupational exposure limit.

In the same residential development it is possible there could be a primary school and crèche facilities. Persons working or visiting/attending these facilities would be expected to be protected by occupational health and safety legislation applied by the responsible person (building user/facilities manager).

Let’s also not loose sight of the fact that occupational exposure limits are worked out on the basis of adult exposure. I believe it would be extremely difficult (if not impossible) for occupational health experts to try and establish occupational exposure limits for infants and young children (who have under-developed immune systems). Under these circumstances, the only true form of control/allergy management is avoidance.

The responsibility (under health and safety legislation) would rest with the farmer who should have conducted a risk assessment to establish what control measures would be satisfactory under the circumstances outlined above.

[deek]

CT, if we now consider substantial equivalence when carrying out an environmental risk assessment of GM canola (in the UK).

It therefore must follow that GM canola (grown in the UK) would also be recognised as an occupational respiratory sensitiser and must therefore be controlled (in the UK) under the COSHH (Control of Substances Hazardous to Health) regulations which is a statutory instrument in the UK.

Now we are talking serious cause and effect relationships here (the causal agent of sensitisation has been confirmed).

It is my understanding that under the COSHH regulations sits an AcoP (Approved Code of Practice) called the Control of Respiratory Sensitisers which occupational health professionals are expected to follow/implement as a matter of good practice.

In my opinion, scientists conducting environmental risk assessments have a duty to disclose what control procedures are necessary to protect both employees and the public from this recognised respiratory sensitiser.

CT, have you witnessed any reference being made to this legislation in any of the GM environmental risk assessments that you have seen? Perhaps the GM scientists have accidentally over-looked these findings.

[screener]

Originally Posted by deek

No, no CT - the study confirmed occupational sensitisation to canola pollen.

Pollen dispersal (although canola is entomophilous) cannot be contained within field boundaries. I appreciate the windborne canola pollen does not travel far (in comparison to other pollens) but it has been confirmed to travel into residential areas close to canola fields.

If pollen from canola can travel a few kilometres on the wind then a town of ten thousand people in the centre of 15,000 acres of canola might be expected to suffer some canola allergies.

"and whose pollen can also become airborne and potentially travel at least
several kilometres downwind (Treu & Emberlin 2000)."
cricket tragic,,"That is fine, I can be sneezed on by my son. He always starts sneezing just as the canola is starting to flower. The trouble is it doesn't matter whether we have canola, wheat or barley growing around us, he sneezes every year anyway. His problem is grass pollen. "

Isn't it the vagaries of fate though. I'd like to be able to say the same, but my daughter is able to speak for herself, and while she also suffers from birch and poplar pollen, is quite definitely affected by canola. I'll ask her to partake in an experiment. This year I am growing non- gm canola. I'll see if she would be willing to test her allergic reaction in comparison to the usual stuff around here.

[deek]

Hi screener, I think the extent of allergic reactions (IgE-mediated) in Canada would be very much dependant upon the cultivars of canola grown and the environmental conditions.

Please bear in mind that the scientific opinion appears to be that the pollen is unlikely to be the main causal factor of the allergy type symptoms experienced in the UK. This does not imply that the pollen does not cause IgE-mediated responses, it merely clarifies the situation that other reactions other than IgE are likely to be the main cause/contributor of symptoms.

[Cricket Tragic]

deek, a bit of clutching at straws here? Occupational exposure, whatever the cause, has no significant bearing on risks to the general public because the conditions of exposure are very different. Secondly, the studies in Scotland have indicated that symptoms did not coincide with canola pollen in the air.

Sensitization through occupation exposure to pollen alone is possible, but will be much rarer than exposure through grain dust. To receive enough exposure, you would need to be working with flowering canola over a significant period of time. Now I couldn’t find any clear evidence in the literature of cases where sensitization occurred solely as the result of occupational exposure to pollen. It may do so, but cases are likely very rare. The same would be true for sensitisation to wheat pollen. Cases of wheat pollen sensitivity are very rare among the general public, but many of the cereal breeders I know are sensitive to pollen of wheat. This sensitization occurs because of years of exposure to the pollen.

Your whole discussion about the responsibilities of various people to protect the public from exposure to canola pollen is equally true of wheat pollen. With wheat pollen there is greater evidence for occupational exposure causing sensitization, wheat pollen travels further and there would be more wheat pollen around residential buildings, although I expect no one has bothered to measure it. So why are their no responsibilities on anyone to protect the general public from wheat pollen? And what about species where we know the pollen does cause allergies in the general public? What about responsibilities for protection of the public from grassy pastures?

[Cricket Tragic]

screener, almost anything is possible. Pollen can also get into the jet stream and fall out over Antarctica. On that basis, you could suggest that workers at the scientific bases in Antarctica might be expected to suffer some canola allergies. The point that I have been making is not that this is impossible, but that there are not the cases to support this being a major risk.

A search of the medical literature indicated the following with respect to canola (oilseed rape) allergies:

1) Food allergies. Canola seed contains 2S albumins that produce a skin-prick reaction on some children with food allergies. These are known allergens from many seeds. Nut allergens belong to this class, for example. Children with this sensitivity were frequently sensitive to a wide range of foods.

2) Occupational exposure. A number of cases of occupational exposure, principally to grain dust in the grain handling sector, but also in situations like pig farming, occur. A small number of these appear to have sensitivity to pollen as well.

3) Broad cross reactivity from other pollen allergies. This by far represented the greatest number of those reporting allergies to canola pollen.

Sensitivities to canola pollen are not turning up in significant numbers in the medical literature. They are not turning up in data from Health Departments. This makes you question how prevalent this condition might be. It is possible, but there just don’t seem to be cases. Hence my suggestion that this is a minor public health issue at most. There are much more dangerous things going on out there with much more evidence for negative impact. A focus on dangers from living next door to a canola crop to me risks taking the eye off the ball of the other, much larger dangers around.

[deek]

Originally Posted by Cricket Tragic

Sensitization through occupation exposure to pollen alone is possible, but will be much rarer than exposure through grain dust. To receive enough exposure, you would need to be working with flowering canola over a significant period of time.

CT - Are we in agreement that canola pollen is a recognised occupational respiratory sensitiser and therefore has the propensity to cause occupational asthma?

[deek]

Originally Posted by Cricket Tragic

The fact that the villagers reported symptoms coinciding with flowering of canola may be significant or it may be that canola flowers are so visible that their minds put 2 and 2 together. Humans are very good at finding patterns, even when no such patterns exist.

CT, I appreciate that your are drawing your thoughts from the literature, however, I wish to point out that this hypothesis has no scientific basis, even although this has been suggested as a possible cause by the IEH Committee and this same claim has been repeated (in parrot fashion) by Hemmer in the BMJ.

The IEH committee appear to have conveniently pushed aside the fact that horses also appear to be affected by canola crops (in the UK) and this has been the subject of intense scientific study also. Come on, are we saying that horses are also psychosomatic and put 2 and 2 together like humans.

But I am pretty sure (as night follows day) CT you will attempt to counter this argument also.